Internal-geared tuning peg



April 28, 1931. H. BERTRAM INTERNAL GEARED TUNING PEG Filed Feb. 11 1929 louis 7-1 Berfram,

I N VEN TOR.

A TTORNE Y.

Patented Apr. 28, 1931 UNITED STATES PATENT OFFICE SON, INC., OF LONG ISLAND LOUIS H. BERTRAM, OF LONG ISLAND CITY, NEW YORK, ASSIGNOR TO A. D. GROVER &

CITY, NEW YORK, A CORPORATION OF NEW YORK INTERNAL-GEARED TUNING PEG Application filed February 11, 1929. Serial No. 338,964.

This invention relates to improvements 1n tuning devicesfor stringed musical 1n- .struments and has particular reference to a tuning peg of the internal gear type.

My invention has for its object to provide a tuning peg of this character which is applicable to the peg head of an instrument without the use of fastening means, e. g. screws, bolts, etc. ordinarily used for the purpose. I accomplish this obj eot by means comprising a screw device which operates to clamp the tuning peg to the peg head of the instrument.

-Another object of this invention is to provide a tuning peg, which is particularly applicable to instruments requiring especially delicate tuning of the strings, wherein the button shank is rotated at the normal speed and the string shank rotated at a very much slower speed through the operation of a novel internal gear connection arranged between the two shanks.

A further object of the present invention is to provide in addition to the internal so pe gear connection, an arrangement of the button and string shanks which will enable them to be disposed in direct alignment with each other, thereby retaining the general appearance and normal operation of a tuning g. A still further object of my invention is to afford a tuning peg arrangement comprising a housing enclosing a driven pinion meshing with an idler internal ring gear, the latter, carrying a second pinion in mesh with a second internal ring gear which is integral with a string shank directly alined with the axis of the said driven pinion.

One embodiment of my improved internal gear type tuning peg is illustratively exemplified in the accompanying drawings, in which, Figure 1 is an elevational view of the invention as applied to the peg head of an instrument; Figure 2 is a substantially longitudinal sectional view of the peg taken on lines 22 of Figure 1; Figure 3 is a top plan view of the peg; Figure i is a plan view of the idler internal gear and the pinion meshing therewith; Figure 5, is a side elevational view of the same; Figure 6 is a detail plan view of the housing for the gearing; Figure 7 is a substantially transverse sectional view of the housing taken on lines 77 of Figure 6; and Figure 8 is a substantialiy transverse sectional view of the assembled peg taken on lines 88 of Figure 2.

Referring to the drawings, 10 denotes the peg head of a stringed instrument in which the desired number of peg openings 11 have been drilled, the openings being of uniform diameter throughout their length and projecting from face to face of the head.

Projecting through each opening 11 is a tuning peg of the improved construction constituting the present invention and comprising a button shank 12, string shank 13 and intermediate housing 14. The housing 14 comprises a cup shaped cylindrical shell having an upper concentric well 15 projecting to substantially midway the depth of the housing and a lower well 16 eccentrically disposed with respect to the common axis or the iousing 14 and upper well 15, and sunk to a depth spaced from the closed end wall 17 disposed in the direction of the button shank 12. A further stepped opening 18 is provided in the end wall 17, the axis of the opening 18 being offset along a common diameter which bisects the axes of the eccentric well 16 and upper well 15, the axis of the opening 18 being further disposed on the side of the axis of the well 15 opposite to that in which the axis of the well 16 occurs. The inner diameter of the stepped opening 18 has the greater dimension, the smaller portion being of a diameter to accommodate a turning fit with a shoulder 19 disposed on the upper end of the button shank 12, while the larger opening accommodates not only a washer 20, but atlange 21 at the extreme end of the shoulder portion 19 of the button shank 12. Beyond the said shoulder in a direction away from the housing 1d the button shank 12 is square in transverse section and projects into the square broached opening 22 in a thumb button 23 of the usual construction. Communicating with the inner end of the opening 22 is a comparatively small opening 2 1 accommodating the threaded shank 25 of a screw 26, the shank 25 bethe block 28 and adjacent face of the hous ing 14 a washer 80 is arranged, the washers and 30 both serving as friction units between the housing and the surfaces affected by the action of the spring 29 in both direc- The shoulder or enlarged portion 19 of shank 12 is provided with an an a-l bore 31 to accommodate the shank 32 of a pinion gear 83, the shank being fixed to he shoulder 19 by a pin 34 disposed transversely through the shouloer and shank, as shown in Figure The gear portion of the pinion projects outwardl in an axial direction from the face of the iiange 21 so as to bring the pinion within the well 16 and nesh with the internally disposed teeth of an annular gear 34. The internal gear 34 is provioec with radially disposed keys 0 lugs 35 which into keyways or slots 36 disposed in the depending annular wall 37 of a disc shaped idler block 38, the latter having a diameter to provide a running fit with the wall of the well 16 into which it is mounted. Projecting into the upper well 15 and carried concentrically of the disc block 88 is a second pinion gear 39, turning with the said block 88 and in mesh with a second internal annular gear40 which in turn is fixed within the depending annular wall 41 of a disc 42 integral with the inner end of the string shank 13.

Between the disc 42 and string shank proper the latter is increased in diameter to provide a bearing surface or collar 43, which, while it is of no appreciable height, functions to hold the string shank firmly in its proper position. The string shank 13, as will be clear from the illustration in Figure 2, is substantially smaller in diameter than the peg opening 11 in the head 10, and in order to form a bearing for the said shank 13, the open end of the housing 14 is provided with a cover plate 43 provided with an interiorly threaded cylindrical upright portion 44, an unthreaded portion of which embraces the collar 48, and the exterior of the portion 44 fitting snugly in the peg opening 11 at its lower portion. The cover plate 43 is permanently attached to the wall of the housing 14 through the connection comprising a groove cut into the interior of the wall adjacent the open end. The

groove 45 being substantially Vshaped, it receives the beveled edge 46 of the cover plate 43, and allows the outer wall of the said groove 45 to be turned inwardly slightly to overhang and hold the periphery of the cover plate fixed. The cover plate 43 is provided with a projection 43 on its upper face to embed itself into the adjacent surface of the pe head to prevent relative movement of the housing. The string shank 13 is further supported by means of screw bearing 47 which comprises a nut 48 and an exteriorly threaded shank 49, the nut and shank being provided with a bore to support the string shank l3 beyond the collar 43. The threads of the shank 49 screw into the threaded bore of the cylindrical upright portion 44 of the cover plate 43, and underneath the head or nut 48 and adjacent the outer edge of the peg opening 11, a gasket 50 is inserted, the latter being an annular member of inverted L-shaped material which hugs the peripheral edge of the opening and insures a subtsantial angular centering piece against which-the nut 4-8 is turned to tighten the connection between the bearing 47 on one side of the peg head 10 and the housing 14 on the opposite side.

In accordan e with the construction just described, the axes of the stepped opening 18 and cylindrical upright bearing 44 are in direct alignment, thereby bringing the string shank 13 and button shank 12 also into coalignment, a condition highly desirable in the trade because of the uniformity of the pegs. By reason of the screw connections between the bearings 47 and housings 14, the pegs may be attached to the instrument head 10 without the use of further fastening means, such as screws, bolts, etc. commonly utilized in devices of this particular type.

In operation, very much slower rotary movement of the string shank 13 than the normal rotary adjustment of the button shank 12. Rotary motion of the button shank 12 and pinion is imparted to the annular internal gear 34, which, being larger than the pinion, rotates more slowly. Likewise the second pinion 39 rotating at the speed of the first internal gear imparts a still slower rotary movement to the second internal gear 40 :7

which is integral with the string shank l3 and of a larger number of teeth than the said second pinion 34-. As a consequence, the strings may be turned very much more accurately since the string shank, as just ex- I plained, moves at a very much reduced rate of speed, as compared with the ordinary rotary speed of the button shank.

lVhat I claim and desire to Lett rs Patent of the United States, is:

1. The combination with a peg head of a stringed musical instrument having a uniform opening therethrough, of a tuning peg device therefor, comprising a string shank and button shank in coaligmnent with each the geared peg affords a secure by L other, a geared connection between the shanks, a housing for the connection, and means embracing the string shank and projecting through the opening in the peg head to adjustably engage in and clamp the housing to the said head.

2. A tuning peg for stringed musical instruments comprising alined string and button shanks, a housing intermediate the adj acent ends of the two shanks, internal gears arranged in the housing and having their axes eccentrically disposed with respect to each other; one internal gear turning with the string shank and in mesh with a pinion gear turning with the other internal gear, and a pinion gear turning with the button shank and in mesh with the last named internal gear.

3. A tuning peg for stringed musical instruments comprising alined string and button shanks, a button for the latter shank, a housing intermediate the adjacent ends of the two shanks, internal gears arranged within the housing and having their axes eccentrically disposed with respect to each other, one internal gear turning with the string shank and in mesh with a pinion gear turning with the other internal gear, a second pinion gear turning with the button shank and in mesh with the last named internal gear, and friction means between the button and housing to resist the tendency of the string shank to unwind under tension of the string.

4:. A tuning peg, as claimed in claim 3, in which the friction means comprises a cup shaped member embracing the button shank and having its open end disposed in the direction of said button, a washer between the member and the housing, and a coiled spring in the member tending to urge the button and its shank axially and away from the housing and to press the washer into frictional engagement with the housing and the cup member towards the housing to bring about further frictional engagement with said housing.

5. A tuning peg, as claimed in claim 3, in which the friction means comprises a flange on the button shank inside the housing, a washer between the flange and housing, and a cup shaped member embracing the button shank and having its open end disposed in the direction of said button, a washer between the member and housing, a coiled spring in the member tending to urge the button and its shank axially and away from the housing to press the first washer into frictional engagement with the housing and the cup member toward the housing to bring the second washer into frictional engagement with the said housing.

6. A tuning peg, as claimed in claim 3, in which the housing is open at its end adjacent the string shank, and is provided with a cover fixed in the open end, said cover having a tubular projection disposed axially of the string shank and having a section in bearing contact with the shank, a clamp screw adjustable in the'end of the tubular projection and having a bore to provide a bearing for the string shank.

7 A tuning peg for stringed musical instruments, comprising a string shank, a but ton shank alined with the string shank, an internal gear connection for operating the string shank from the button shank at a reduced rate of speed, a housing disposed against one face of the peg head of the instrument and provided with a tubular projection embracing the string shank and disposed in an opening in the peg head, and a clamp screw having a bore to provide a bearing for the string shank and adjustable in the tubular projection between the latter and the shank, said clamp screw being provided with a flange to engage against the peg head on the face opposite the housing, and a gasket projecting into the bore of the peg head opening and over the top between the head and the flange.

8. In a gear operated tuning peg, the combination with a strlng shank and an axially alined button shank, of a housing intermediate the adjacent ends of the two shanks, said housing having two superimposed recesses eccentrically disposed axially with respect to each other, a rotary block in each recess, each of said blocks having a depending skirt portion provided with diametrically disposed slots, an internal gear ring for each block having oppositely projecting lugs to engage in the slots of the blocks, a pinion turning with the button shank and in mesh with the last named in- LOUIS H. BERTRAM. 

